A circuit board may have an electromagnetic shielding layer to reduce electromagnetic interference (EMI) in the circuit board. The sidewall of the EMI layer may include a number of mounting legs. The side wall of the circuit board needs to define a number of receiving grooves for the mounting legs. The mounting legs are inserted into the receiving grooves to connect the electromagnetic shielding layer to the circuit board. However, the mounting legs and the receiving grooves increase the cost and the complexity of manufacturing process. Improvement in the art is desired.